Hydraulic safety valve



Sept. 4, 1951 R. GROSSE 2,566,609

HYDRAULIC SAFETY VALVE Filed June 20, 1947 swam W rease Patented Sept. 4, 1951 UNITED STATES PATENT OFFICE 2,566,609 HYDRAULIC SAFETY VALVE Rudolph Grosse, Jacksonville, Fla.

Application June 20, 1947, Serial No. 756,000

1 Claim. 1 This invention relates to hydraulic valves, and more particularly to a pressure operated safety valve for use with the hydraulic brakes of an automobile or other vehicle.

It is an object of this invention to provide an improved pressure actuated hydraulic shut-off valve for connection between the master cylinder of a hydraulic brake system and the wheel brakes. The valve is so constructed and arranged that a break or excessive leak in the line from the valve to a brake will cause the valve to shut off the flow of fluid to either the front or rear brakes. Rather than close the supply to one brake, it is preferred to close the supply to a pair of wheels so that an even braking force will be had by the vehicle either at the front or rear wheels. In this manner the sudden swerving caused by uneven braking on opposite sides of the car will be avoided.

Another object of this invention is to provide an improved hydraulic valve of this kind which is very simple in construction. The valve is formed with but one moving part, actuated by the pressure of fluid through the valve housing. There is no necessity of adjustment, and as the tolerances of fitting are very large, there is little cause for wear of the parts.

Still another object of, this invention is to provide a valve of this kind having a screen about the opening from the master cylinder to exclude from the valve and connected lines any foreign particles or sediment which might accumulate in the master cylinder and from the reservoir.

A further object of this invention is to provide a valve of this kind for preventing excess oil from escaping from a broken hydraulic line. An excessive amount of oil escaping from one broken line would dissipate all the oil from the brake system rendering the entire system inoperative, and by the use of this valve, only that defective line and its associated parts are cut out from the system leaving the remainder operative.

With the above and other objects in view, my invention consists in the arrangement, combination and details of construction disclosed in the drawings and specification, and then more particularly pointed out in the appended claim.

In the drawing,

Figure 1 is a side elevation of a hydraulic safety valve constructed according to an embodiment of this invention,

Figure 2 is a vertical section taken on the line 22 of Figure 1,

Figure 3 is a fragmentary transverse section taken on the line 3-3 of Figure 2.

Referring to the drawing, the numeral I0 designates generally a body of a hydraulic safety valve for use in the brake system of an automobile or other vehicle for shutting off the flow of hydraulic fluid to certain brake lines upon the failure of those lines.

The brake valve in is adapted to be disposed between the master cylinder of the hydraulic system and the cylinders of the wheels. The valve H3 is adapted to be connected between the front and rear wheels. The two brake lines connecting the rear wheels are connected to one port of the valve 10, and the brake lines from the front wheels are connected to the other port. In this manner the failure of one of the rear brake lines will result in the closing of the valve to prevent the flow of fluid or pressure by applying either of the rear brakes. The same arrangement applies to the front brakes so that the failure of one of the front brake lines will result in'the stopping of fluid pressure to both of the front wheels. In this manner the loss of fluid is prevented, upon the failure of one brake line and application of the brakes after the failure of one brake line will result in an even application of pressure to at least a pair of wheels, one on each side of the car. Since the brakes are applied evenly the swerving of the automobile due to an uneven application on either side will be avoided.

The safety valve I0 is formed of a rectangular metal block H, having intake and outlet ports formed therein. The block II is formed with a transverse bore I2 near one end thereof, and with a right angularly disposed vertically extending bore l4 which communicates with the bore 12 intermediate the length thereof. Both ends of the bore l2 are threaded as at l5, and a connector fitting H5 is adapted to be engaged with the threads H5.

The fittings iii are each formed with a reduced diameter inner end I'l threadably engaging with the bore I2 and threads I5. The fitting I5 is enlarged at the outer end and threaded internally for the connection of the fiuid lines to the wheels. The inside of the reduced diameter end of the fitting It is formed with a further reduced diameter opening l8 which extends outwardly from the valve seat I9 formed on the inner end of the reduced diameter portion H.

The valve seats I9 are rounded and faced inwardly of the bore I2 and block II. The inner ends of the fittings l6 are spaced apart in the block II by at least the diameter of the inlet opening or bore M. A cylindrical screen or filter element 20 is disposed within the bore l2 between the inner ends of the fittings 16. The outer ends of the screen 20 abut the inner ends of the fittings [5 to prevent any sliding movement of the screen 25 in the valve 10. A sliding plug 2| is disposed within the transverse bore [2 for alternately or selectively seating in the valve seats IQ of eithenpneoigthe fittings It.

The outer ends of the plug 2| are rounded as at 22 to conform to the shape of the valve seats IS. The plug 2| is of a smaller diameter than the diameter of the bore I2 and less than the internal diameter of the screen 20, so thatifluid may normally flow freely about theplug 2'0 and outwardly through the fittings I51 "The ends 22' are so shaped that the plug 2| will sealinglyengage in the valve seat [9 when the plug-ans moved outwardly by tllf flow of liquidin one direction due to the dropfof jpr'ssure inth'e broken connecting lineq Thebore Mfis threaded'internally at its upper end as at 26, 'and' 'a connector'fittingi'zfi'is engaged with thethread'sfflf'for connecting a line asZB' to the master cylinder." An extension of the bore 14 is provided; beyond the intersection of the bores Ill and I'2,"as"designated bythe numeral 2?. Tliejb'orel'l e gtendfs downwardly fromthe bore l4 throughithefblock' H. A pressure responsive switgzli{28 is connected to the bore 2'! by a suitable "connecting means or fit,- tings 29. The;swit'ch 28 is provided with contacts 29 and 30 for conne'ction,with the electrical circuit tothe brake light.

In the use andoperation, of this valve i8, the line" 26 connects between thefvalve lt and the master cylinder of'thejrakei'systemi The bore llpr'ovides a'n'jinletpoitffor the hyd Taulic fluid. The fittings feareconllccted tofhydraulic" lines 3! which extendtojthaw ljbrake's." Upon 'applicationof pressure toth inas'tencylinder, hydraulic pressurejis appliedjthroughj the valve It. This pressure wil1:actuatef theswitch28101 completing the circuitjtoithe b'rake'lightst The'pressure and flow fof fiuidf;through'b'othiot'thefittings It) will be thesame so thatjthefplug ,2! will remain substantially between thjelinnenend of ,the fittings l0. Uponlthe failure'jojf one 'offthe' hydrauljic lines, theipre'ssurjtq' tha1;, 1ine will drop and the flow ofli'quidto that line willsuddenly increase with a resulting decrease of pressure; The resulting pressure: in the other." hydraulic lines willact on the plug 2| for-moving the plug toward the valve seat I 9 and fitting I6 connected to the low pressure line. The remaining pressure in the system will hold the plug 2| in sealing engagement with the valve seat l9 so that a further loss of liquid will be prevented.

I do not mean to confine myself to the exact details of construction herein disclosed, but claim all variations falling within the purview of the appended claim.

' What I; claim;'is:

A hydraulic safety shut-off valve comprising,

a body formed with a transverse bore there-'1 through, anoutlet fitting engaged in the opposite ends '01 said bore, each of said fittings formed with, an. inwardly directed valve seat on the REFERENCES CIT-ED The following, references. are of .record in the file of this patent:

UNITED. STATES PA'rn Ts Number Name Y Date 820,146 Simond s May a, 1906 333,337 Peck}; Marj3l. 1908 966,150 Woodbridge, Aug. 2, 1910 1,588,657 Christensen June 15, 1926 1,609,641 Christensen Dec. 7, 1926 1,664,680 Hallett Apr, 3, 1923 1,686,310 Beebe Oct. 5, 1923 1,782,758 Gavin Nov. 25,; 1930 2,145,790 Groves Jan. 31 1939 2,190,822 George Feb; 20; 1940 2,254,990 Blank- Sept. 2, 1941 2,265,117 Seymour, Dec..2,.19f41 2,322,658 Qverbeke June 22,- 1943 2,381,432, Blank- Au 7, 1945 2,366,535 Blank Oct. 9,19%

FOREIGN PATENTS Number Country 1 Date.

333,365 Great Britain 6fijl930 349,520, GreatBritaln, of." 1931 

